You just described my sd10 Grandma washes are hair, dresses her, hand feeds her like a two yr old. Yet she has her wearing make up, string bikini underwear, high heels, bras. I think its insane.

I agree that 10 is a bit young. DH would absolutely flip if his daughters came home wearing makeup. He gets huffy when I let them put on tinted lip gloss (while playing at home, not going out).

Oh my... this sounds exactly like my DH's grandma (SD10's greatgrandma). One hand she washes SD's hair, cuts up her food, etc... then she lets her stay up as late as she wants (which is usually past 2 am because she knows she can sleep til noon if she wanted to.)

I know grandma means well, but come on!!! DH has told his gma that this is inappropriate so many times, but it literally goes in one ear and out the other. We've threatened to take SD away, so she starts putting her to bed at a "normal" time... but then it slowly gets back to what it was before and then we start all over again.

It's so bad that because we're going on vacation tomorrow after work, DH had to call gma just about every night to make sure SD was going to bed at a decent time, and waking up earlier.

*SD stays at grandma's during the week, then she is with us on the weekend... this way she doesn't have to get up at 6 am to head to grandma's each week day. We pick her up every Friday afternoon and drop her off Sunday evening.

Talk about overstepping...I think it needs to be addressed with Grandma rather quickly.

I will do dd9s make up. She's so girly and loves having her make up done. However this is as a nice treat when we are at home. She doesn't wear it when she's going out anywhere. It's just for fun like dressing up she has her own make up again only for when at home to "play" with. I don't think children should wear make up until they're older to go out (my opinion) She can wear lip gloss/balm whenever though x

I think 10 is too young for makeup. Let her use the makeup at home for play but it gets washed off before going into public. 
Also this will be my SD in the future. Still has people buckling her seatbelt at 8 but will be into makeup.

Gramma is sexualizing this 10yo. 

Sexualization of children has been an increasing problem over the decades, exacerabated by the hormones in the food chain that cause girls to mature at ever younger ages. For some reason it does not seem that boys are impacted as significantly as girls by this.    Nothing official, just my observations.  When I was in my late teens and through my 20s I had crappy jail bait RADAR.  My longest term HS GF was one.  I was 18 when we met, she was 14.  I had no clue.  She was a Sophomore and I was a Sr.  We had been dating a few months when her mother called to invite me to her birthday party.  That is when I learned she was about to turn 15.  I turned 19 a few months after she turned 15.

I ran into the same thing not long after my XW moved out of our home and filed for divorce.  I met a "woman" at a night club.  I was 26.  It never dawned on me that she was not legal.  It  turned out that she had just turned 17, which I did not learn for a few months.  As soon as I learned she was that young, I ended it.

Then there is my nearly "jail bait" DW.  I first saw her at the beginning of the last semester of my 11yr undergrad career. It was her first semester of college after graduating from HS.  After a couple of weeks of running into her around campus I asked her out.  She gave me her number.  The first evening we had a phone call with each other she dropped the "I have a kid" bomb.  That was fine with me, I had no issue with her having a past.  I did not learn that she was only 18 for about a week. We met a few months after she turned 18. I was 29 at that time. I turned 30 3mos after we met.

Kids need to be kids until they are at an appropriate age to start expanding their horizons as they progress towards being adults.  10.... is too damned early for that IMHO.

Is DH too much of a mama's boy to put his mother straight on any of this?

If not, you may want to find a real man rather than a mama's boy.

Almost everytime SD8 comes back from BM's place, she's wearing makeup (lipstick, eyebrow pencil, ...). I always thought it was weird. A few months ago, I think she wasn't 8 yet at the time, her parents were thinking about making her shave her legs. Luckily, it didn't happen: when BF asked my opinion about it, I managed to retain a huge "WTF??" and politely tell him it was too early for that, and he listened to me. I don't know what is going on with people.

It blows my mind how some kids these days are overly babied AND pushed into premature adulthood simultaneously. My makeup-wearing and supposed-to-shave-her-legs SD still hasn't finished her potty training process and still shits her pants almost daily. She walks around sitting in her own poop while talking non-stop about having manucures, buying new clothes, wearing high heels and dying her hair.

This sounds like my SD and BM. She didn't wear much makeup and definitely not around her dad because he wouldn't have gone for that but at age 9-10 she was getting full sets of fake nails and shaving but didn't know how to do her own hair or shower properly. SD had 3 holes in each ear by 11 and got her nose pierced at 14.

I have no issues with kids wearing makeup to play even if it is bright crazy colors but definitely not out of the house. That kind is stuff makes them look older and when they're not emotionally ready to deal with the attention that it can bring it's not appropriate.

NoName, IMO, your MIL is evil and I'd never let your SD stay the night again and I would limit the access.