Introducing Rats

[rattietatties]

So I got a pair of babies a few weeks back and they're about 8 weeks now so I've started to introduce them to my older two. One of my rats is definitely on the larger size and he freaks the babies out every time they see him and in turn, they get spooked if they see my smaller boy. They've been meeting in a playpen but the walls are short enough that the babies can leap out of it which they've been doing every time they get put into the pen. Is there anything I can do to try to get them more used to him? Their cages are currently next to each other and I've been switching fleece blankets between cages. I know 8 weeks is like the bare minimum for the appropriate age for introducing them so is it just that they're too young and I should give them another week before starting intros again?

 

[Twilight]

I'm not entirely sure when to start intros, etc. but I do know there's some good, detailed info on intros on joinrats.com