Tough question. I once desperately wished they didnt exist. Im now very close with the eldest, not in a motherly sense, more like a big sister (which sounds odd I guess but my little brother is 14 years younger than me so in terms of age difference, I guess thats the only relationship I can liken it to). I love him to bits, hes a great kid. I dont love him like a mum but I dont feel the need to, we have a great bond.
The youngest... Oh god. Im awful but no, I about tolerate him for the majority of the time. Sometimes fond, mostly grin and bear it, other times I just have to be away from him. He has additional needs which make him... I guess just a lot harder work, which in itself isnt an issue, but means he has no off button, zero emotional awareness, is constantly acting the fool for attention and thats all fine when you are in a good place and can mentally understand its the issue rather than him, but when its constant, god it just grates, its exhausting. He's a walking mouthpiece for his mum, not deliberately, but if shes said it, he's gonna come and tell us. We'll ask him why what hes said was even relevant to tell us and he doesnt know, its just basically word vomit. No one will have said anything at all for the last few minutes and he'll just blurt out "Mum told brother off last week for him accidentally calling her "my name" and said it was a disgusting thing to call her". Just out of nowhere, so constantly having these little bombs dropped in when we all just having a perfectly nice time. When told I miscarried, and both were asked if they had any questions for us, youngest instantly sparked up with "I bet it was weird carrying around a dead baby inside you, hurhurhur".
Im due my own next year (all being well this time) and I worry that it will highlight the issues with youngest SS further. Hes not going to take the baby having attention well. Last time he spent time with my much younger niece, someone commented on not realising how big kids are getting until they are around other younger kids, and he started crawling around on the floor saying he was still the baby.
In saying that, I'd never let any harm come to him. But I dont think I'll ever love him anything like my own.