Late night phone call from his ex

Last night, my SO's ex wife texted him at 1130 to share a random, unimportant tidbit about their sons sports tryouts. The lateness of it had me suspicious so I did some digging and found out that she called him at 10 at night the day our daughter was born, 3 months ago.

I sent him home for the night to sleep while I was still at the hospital after c section caring for our newborn. She and their sons came to visit that day.

She texted him at 10pm to make sure he was at home not around me, then called him... the call log says an hour. I confronted him and he said the phone call was all reminicsing about when their boys were little. I feel that's inappropriate along with the circumstances surrounding the phone call, the length and the time of night.

I'll be honest that I'm furious because this is compounded on top of the fact that she bought him a little personal gift for no reason a couple weeks ago...she made sure I knew it was from her and told me she was 'thinking of him'.

He asked her for advice about taxes and a little advice about mutual funds, that ticked me off, too.

My question is how inappropriate is that phone call?