Love for step children?

Right, so I follow this lovely fitness girl on Instagram and yesterday she posted about how she doesn’t love her step son (like 8 years old) the same way she loves her bio son (2 years old) and how guilty she used to feel about it. I think it’s great that she speaks up and all the comments agreed with her but I also think it’s possible to love a step kid as your own.

I’m divorced and I have an almost 3 year old boy from my previous marriage and currently pregnant with my 2nd. My fiancé says he loves my son as his own, he changes his poop, picks him up from nursery, makes his food, reads him to bed every night and so on. I’m just a bit worried about having our 2nd child (my fiancé’s 1st bio child) and him loving more one kid than the other.

What’s your honest views in the topic?