My almost 4yo has always been quite a gentle soul and quite attached to me, but he used to be really confident and sociable. Over the past few months, he's started regressing really badly: he's started calling me 'mama' again, constantly tells me he loves me, always wants to be sitting on my lap. If he doesn't want to do something, he'll shake his head, go silent and shake, making a little whining noise. He can speak really well, but is doing a lot more whiny noises than explaining what he means at the moment. He's also become really resistant to everyone else, including people he usually loves like his dad or my mum- he basically only wants to be with me.
Obvious causes that I can see: he has a sister who has just turned one, and I've gone back to work, which he absolutely hates. I try really hard to give him special time by himself without his sister, talk a lot about our feelings, tell him I love him. What else can I be doing? This has been going on quite a long time now and I'm getting worried.
Nursery say he doesn't do it there.
Any thoughts welcomed!