I'm picking up on the inheritance - people have ir own 'blood' family to leave them money - why would people share inheritances received from their own parent/GPs with their step and half siblings.
This is always one way traffic , I've noticed with these blended families. I'm going to get muddled explaining this so bear with me. So man & woman make a new family, each bringing a child to that family, they then have joint child. Its always expected that the extended family of the Joint Child is accepting of there children brought to the relationship and goes so far as to actually treat them as blood to the point of leaving an inheritance.
No one ever says, well the dad of the first child is well minted, so if Elder Child inherits he must share with Half (joint child) Sibling No one ever says to original mum, well if you're buying X present for your child, you must buy the same for the new half sibling. It simply doesn't work like that. You can be loving and polite, but you are not obliged to leave your money to anyone other than the person you choose.
It's all very one way traffic.
TBH, if my sons friends are anything to go by, some of them have 5 or 6 half siblings, each with different mums and dads, not to mention an equal number of transient step parents (mum new boyfriend) and a similar number of step siblings.
At another wedding the photographer's assistant issued 'numbers' to people and you had to listen for your number to be called. Father and son were included in family photos and elder son and I were not. I had this visceral response and tried to wrestle younger son out of photo.
Beyond ridiculous. You actually got physical in a wedding photo shoot over a family photo? There are many different dynamics of photos, all bridesmaids, in laws, ushers, bride /groom with siblings (and no partners) and so forth.
I think it's been covered up the thread, bended families are created for the adults involved without much thought to the kids and whether they want to be in this relationship or not, whether they want to acquire siblings (half, step or otherwise).