I know that the title is a bit click-baity, but that's the jist of it.
I have 2 stepchildren that live with us full time. I also have a 2, almost 3 year old. Her birthday is coming up and she was showing no interest in a party so I planned to take her and her 4 year old sister horse riding instead as she is obsessed with horses and it will be the first time she is old enough to ride them at the local stables.
I told DH and he said I would also have to book my 9 year old stepson as he hasn't ridden horses before either. The girls have a great relationship with him and I do a lot with the three of them together so that's fine and I booked them all in for the day of her birthday. Now my 14 year old DSS says he wants to come and DH has said I should also book him in. Here's my issue, DSS14 is awful to his siblings at times, he is basically a bully and tries to control and domineering his younger siblings. Aside from that- we had issues with DD2 hitting and biting and scratching and nothing we did was stopping it, then 2 weeks ago I heard DSS14 whispering to DD2, DSS9 was there and said loudly to DD2, "no, you don't do that, don't do what he's telling you", and I asked what was being said and it turned out that DSS14 was telling DD2 that if anyone ever upsets her she should hit or bite or scratch them. Since then DD2 has told me and my parents on separate occasions that DSS14 tells her bad things and when asked what she said he tells her to hit mummy or to hurt other people.
DH spoke to DSS but didn't give any kind of consequences, he accepted DSS's explanation that he was trying to teach her how to defend herself and telling her to hit back if someone hit her first (that's not what he said and not his place to teach her).
Since I've booked it DSS14 keeps going on about how he can't wait to go and how he'll be better at it than all the others. I feel like not only should his recent behaviour with DD2 mean he doesn't go, but I know that he isn't interested in it being her birthday and the day will just become all about him (this very often happens, it affects family days out, birthdays, celebrations). As the youngest, DD2 has spent her life falling in with everyone else's routine and life, I feel like this one day could and should be about her for a change.