Pick age group then add print to basket. 

If ordering anything that needs 2 slots such as:

rompers in 2-3 and up

Dresses 2-3 and up

leggings 5-6 and up

adult clothing 

Put 2 x the print in your cart so that the quantity is 2 and then 1 age group

For Mystery pants do not add a fabric in your basket.