Advice... single mum.

Hi all,

This is my first post. I have a question for all the single mamas out there on how their ex partners are with their children. My son is 10 weeks old, me and his father split around 2 weeks ago, reason being that he won't take responsibility and sort out a job to provide for us as a family and I no longer can support him as well as our baby. When we all lived together he was always very hands on and never stopped saying how he loved our son and no one else mattered and that he had always wanted a son... however since he moved to his mum's (only a short 5 minute drive away) there are days where he doesn't even ask how our son is? Is this normal? If the shoe were on the other foot I couldn't bare more than a few hours without knowing how he is doing and what he was up to...

My ex has a daughter from a previous relationship that he does not see because her mother does not care to let him make plans with her (or so he says) and since it has now been so long (she is nearly 2 years old) he has not really tried as much as I think he should have to see her... part of me wonders if the real reason he does not see her is because he didn't try nor care enough to be a responsible daddy! I am very tempted to try and get into contact with her for a chat as her daughter is after all my son's half sister :/

What do you guys think? Am I over thinking this?