Missing Infant/toddler developmental milestones seems to be the biggest factor in RAD from my perspective.

I believe one of the most important to work on first is permanency. This is the step when a baby starts to move. They crawl around the corner of a room and play peek a boo with you. They crawl out of sight, then come back and find you. Most insecurely attached children do not have permanency. You can teach permanency easily to big kids.

1 - Play hide and seek. Parents must play with kids. Hide under a blanket on the couch. Hide in the therapist's office. Hide and seek in lots of settings often. They will get this milestone in about 6 months with much playing.

2 - Cover them with the blanket. Cover a stuffed animal too. Show them the stuffed bear. Where is his leg? Have child point to leg and say it's right here on his brown body. Cover the bear with the blanket. Where is his leg? Insecurely attached children will look under the blanket to find it. Slowly, they will develop the concept that even when he's out of sight, he still has his leg in the same place. The same games need to be played with your child. Do them over and over. Cover your head? Where's Mommy? At first they will peek under the covers - "there you are!" Eventually, they'll laugh and say, "under the blanket."

My experience has shown your children will attach if you do this. When I started with my RAD dd, she was healing. This helped her gain huge strides. She didn't know her feet were still connected to her body when covered with a blanket as a young teen. Amazing to me!