I am writing this, prompted by some other blogs and my replies to them. This is something that has been dear and interesting to me for many years, both being a linguist and having been raised in different languages.
This will also make me even more identifiable :? oh well.
I was raised in two countries, one being Italy and the other a northern one.
I'll get to my point now.
English lumps all kinds of feeling under "love". Sure, we also have "care" and other words, but when we tell our loved ones, we say "I love you", be it our child or our husband, or our parent. Now, given, words are just that, a way of slicing up this world in order to communicate with one another and also to connect different parts of our own brain. We end up thinking that what has a name now exists in a way that something we have not named does not. That is always good to keep in mind, how we benefit from language, yet it limits us greatly.
BUT, in Italian, among other languages, we have a different way of expressing love, depending who it is for.
Our kids, our parents, dear friends....we say " Ti voglio bene", literally "I want you good", I have loving, caring feelings for you.
To out mates, we say "Ti amo". We can say the first one to our mates too, depending what we are trying to get across, but "ti amo" is exclusive of mates and lovers and married people.
How does this apply to my initial point about the problem English is partly responsible for here in Step world?
Well, when little sd's go up to daddy and tell him they love him, and look at us, it would be different if they had to use a different word. When DH tells his kids he loves them and then tells us "Ti amo" it would be clear to all involved that we are talking about two different things here. Two different scales. Less room for attempts at little incestual competition. I'll go beyond that. If you are raised with these two very distinct concept in your mind, helped by the fact that your languages separates them, thng get less murky in many ways. I think there would be less competition all together. Kids would know they have their own set of feelings of love from the parent and step parents might be less likely to feel in a competition as well.
I have never heard, in my entire life, a child tell their parent "ti amo". There is a separation there. Again, language is just what we call things, and some languages seem "better" at naming some things and worse at naming others. But we are very much a product of what language has shaped us. If we don't have a word for it, we don't quite think it exists. If we have more than word for similar things, we are forced to make a distinction.
Sorry for the ramble, I think/hope it might help.