No - but she might be.  This is an ADULT.  Great for her for working hard - but at this point in her life SHE is responsible for her vacations.   Tell her that she can go if she can 100% pay for herself - oh wait she can't do that.   The 11 year is still a child - in addition to being free.

There is NO reason for you to feel guilty.  She's being a brat.

Yeah I don't think there are many 20yr olds out there who can say their family pays for them to go on vacay with them. The fact that feels justified in being so upset about it screams entitlement. It will probably do her good to not have a trip to Mexico paid for.

Adulting sucks, she's just learning what we all already know.

My parents did pay for me to go on vacations with them, well into adulthood, BUT, they had lots of money and I never took that for granted or felt entitled to it. In your case, it's not a possibility financially.  So next time, let her know that she's welcome to come if she books her own ticket and room by X date, as you can't afford to pay for her.

Comparing herself to DD is absurd, as DD is a child, and it's FREE for her.  Don't feel guilty. She sounds very entitled.

She is an adult, has her own life, and lives with her BF, you should not feel guilty for going on a vacation without her.

I haven't been invited on a "family vacation" since I graduated High School... They've been on several, my younger siblings went, but once I was out, I wasn't not welcome. But they definitely weren't paying for it. And as tey know my financial situation, they wouldn't invite me anyways, because they know it would be a push.

Ha, I remember when my SD's were 26 and 28 they got upset if we did not invite them.  They, and your SD, are upset that the world is moving without them being the central focus.   Just ignore her.

My step-sister pulls this shit too and we are almost 30 (we were born a month apart) our parents have been together for 15 years....at 20 I was paying my way through college and she was pregnant for my nephew. Because she had kids and the responsibilities that come with them, every time my step dad and my mom do something she feels entitled to part of it or like that money could go to her instead. 

Here is the thing-SD is 20 years old and moved out on her own. She’s an adult. YOU and your DH worked hard to take this vacation, and you don’t owe her an explaination for it. Plain and simple. Maybe next time, if you want to you can plan something together but it’s iust a sickie part of growing up. You did your time working, parenting what not and I’m sure it was hard. Now she’s got to pay her dues and someday maybe she can do the same. But she’s grown. She’s not a child and this isn’t tit-for tat anymore. Or at least that’s what I’ve been telling my step sister for years-in one ear and out the other with her though. 

My step-sister pulls this shit too and we are almost 30 (we were born a month apart) our parents have been together for 15 years....at 20 I was paying my way through college and she was pregnant for my nephew. Because she had kids and the responsibilities that come with them, every time my step dad and my mom do something she feels entitled to part of it or like that money could go to her instead. 

Here is the thing-SD is 20 years old and moved out on her own. She’s an adult. YOU and your DH worked hard to take this vacation, and you don’t owe her an explaination for it. Plain and simple. Maybe next time, if you want to you can plan something together but it’s iust a sickie part of growing up. You did your time working, parenting what not and I’m sure it was hard. Now she’s got to pay her dues and someday maybe she can do the same. But she’s grown. She’s not a child and this isn’t tit-for tat anymore. Or at least that’s what I’ve been telling my step sister for years-in one ear and out the other with her though. 

So first of all, I don't understand these adults even wanting to go on vacation with their parents! The last time I went on vacation with my family was when I was 16 and I didn't even want to go, my parents made me. I can't imagine wanting to go on a family trip in my 20s especially if I was on my own. That's what Killing me about this too, this girl doesn't even live at home AND she lives with her boyfriend! Shouldn't she be going on vacations with him? Bet he feels real special that his girlfriend is all pouty about her FATHER not taking her to Mexico, how embarrassing! Is this guy also emotionally stunted? And then there's the whole passport issue, those are not quick! And if they are its extra. If you're going next week, I don't think she'll get it in time. And do you get to foot the bill for that too? Yay you!

Shes being completely ridiculous. Don't you feel guilty for a minute. This is beyond and she needs to grow up.

At 20 I had zero interest going on vacation with my parents.

These entitled brats! 

My brother has 3 kids. All different ages. They used to take all 3 on vacations. Now they only take one as only one is still minor and lives at home.

Last year at a family dinner we were discussing place that my brother, SIL and my minor age niece went on vacation last year. My nephew’s wife made a disgusted face and said “is that a vacation we were never invited to?”. Jeez. My nephew and his wife are married, have college degrees and very good jobs AND travel frequently. Still she expects in laws to invite her to vacations? 

It's none of her business what you do and where you go on vacation and who you invite and don't invite. She is an adult and should act like one especially after the circumstances were explained to her.

why should you feel guilty? Don't...STOP feeling guilty. Do you need her permission to plan and take a vacation? 

Please don't let her selfish attitude ruin your vacation.

Do I think you should feel guilty? No. Do I think her anger is misplaced? I'm unsure.

If DD has had a more privileged life thus far than SD has, I can see her being grouchy that DD is getting "the finer things" while she hasn't. While we as adults and SPs understand why one set of kids lives differently from another, it's particularly hard to see when you are the kid who feels shafted.

Additionally, if you all have discussing this as a "family" vacation but didn't even invite SD to go (even if you think she can't afford it), then that can sting. She is doing the transition to adulthood which comes with letting go how she has experienced life for the last 20 years. Not being told about a "family" vacation can make her feel like she isn't "family".

I'm NOT saying her passive-aggressiveness to you is okay. That needs to stop. She can feel upset all she wants, but she can also be an adult and let you all know what upset her - and then she can get over it.

I had a very similar talk with my sister two years ago. She was angry that she was having to work so hard for her life when she perceived that I had to work for nothing. She and I had a come-to-Jesus meeting where I set her straight about what help I got versus what she was getting (it had actually been a fairly even distribution, just distributed differently). I acknowledged that she was hurt, but I also put her in her place and told her that she could either get over it and be family or not and...not. Punishing all of us for being upset wasn't okay even if being upset was.

So, my advice is to ask her what hurts about this trip. If she just feels entitled to go, tell her to get over herself. If, however, she is struggling in that transition to adulthood while also feeling like she is being kicked out of the family, reassure her that's not what is happening. Then tell her she can either forge a new path within her new adult status in the family or she can bugger right off. She doesn't get to punish you all just because she got older.

As soon as I turned 18, and I was still in high school, my dad and Stepmom made me pay for my own plane tickets to go on vacation with them. I didn't have to pay for everything the enitre vacation, just the flight. At the time I was pissed, but now that I am older, a BM, and a a SM; it's the way it should be. When children hit 18, they need to have some responsiblity to see how the "real world" actually works. MAYBE in your scenario it could have gone, "SD if you pay half we will pay the other half". Just a thought.