Thanks everyone I figured I would get some vastly different opinions which is good that is the real world.

Firstly my sister is not the child's mother its my sister in law pembrook you seemed like everyone but you was confused about that, and my sil his mother
is so polite she just ignores him. My in laws do lots of disciplinje correction but he is 3 and the cake issues were about a year ago. The cake sunday was for
mothers day so it wasn't anyone elses birthday cake just to clarify.

Some of the remarks I wasn't standing right there, the one about the whole world won't revolve my daughter was there for.

Also sometimes he plays with a phone app on his moms iphone, on another day he saw the twins playing with a play phone and said at least they don't
have a phone like Ryan! I guess I don't think quickly on my feet but clearly he can't stand him. The thing is he is good with kids usually he was great with
one of my nieces he just can't stand that my nephew isn't perfect I guess.

I do tend to agree with cataholic and pembrook but I also understand the others opinions on this and do appreciate them. I have tried to give my sister
in law some tips like when he has a meltdown in a store to just leave.