Trying to figure out what kind of rats I have

I have 3 rats, 2 boys Dewey and Pete which are from the same litter and Abby who is 3 months. I know that the 2 boys are dumbos. The coat on Dewey is normal but I know his mom was curly like Pete is so I know he has the curly gene. With that being said I can’t tell the difference between a Rex and a double Rex. When Abby was about 6 weeks she lost her fur and it grow back but it is a weird coat. Can anyone help me? View media item 777View media item 776View media item 775View media item 774

Hey! Abbey is a rex as well just like Pete. She just went through a weird molt upon getting her adult coat. hope this helps!