Nathan and Millie

The boy's have taken to Nathan arrival really well. But with them being in school during the day claire a d I have been brain storming on ways for millie to get to know her brother.
They have been sharing baths (to which millie was like who's this in my bath look on her face) to doing something like this which seems to work, kinda. I know it's early days and millie is only 20 months old but what you gonna do? I'm a parent. I try to forsee or troubleshoot any problems and iron them out before anything comes of them.
Any way everyone is asleep I think I will follow them zzzz