Toddler being difficult, but not with me! (his Dad)

[Scratcy]

Out strong willed son of 20m is occasionally a bit whiney with me, but generally fine, and we get along great. However, his mother says that he plays her up, whining and having tantrums when I'm not about. This is worse when he is tired. How can I help to stop him giving her trouble??

You can't as I suspect its a phase (dd has played me up and dh at different times but ESP me). You need to back her up when he does - say don't do that to
Mum, ignore him by not playing or cuddling him etc when he does it.
Also hard as It is if she can not react that helps. When I just said oh well I will do something else or didnt react she went off the idea quickly.

I will give that a try Gastonladybird. I hope its a phase as it making my better half miserable.

It lasted a few weeks with my dd -she still does it intermittently (and also with dh) but ignoring seems to work.