adopting older ADD/drug affected children

For people who have adopted older children, if you have any advice- please share, as you will understand my problem here. For those of you raising babies from birth, try to imagine the differences!
This pic of basket full of kittens who are escaping before I could snap the pic, gives a small idea of what it is like to try and change a diaper of a very fast, strong, mobile toddler with ADD issues and wearing (painful) hard braces on his feet. I didn't get to practice while he was small and non-mobile, but am jumping in at this late date while trying to not get poop all over the floor, our clothes or get kicked with a foot brace. So you can imagine how unappreciative I am of the laughter flowing from my near hysterical mom and sister as they roll on the floor. They find it funnier the more problems I have like when the wiggle worm is pushing his feet so he scoots himself away from me taking open poopy diaper with him and I have to keep pulling him back, while trying to make a face that shows I do not think this is a new fun game to play, and his big sis comes in to ask me questions and try to get attention. Behind her comes little niece who only having female cousins has never seen little boy privates before and wants to know if that is his "flower". ( Her Great Gma told her that name and it stuck) I finally get my mom and sister to help me by frowning at them and using a stern voice while telling them, that yes, I need to practice, but throwing me in the deep end with all three sharks the very first time, is probably not the nicest way for me to get experience. They finally helped by distracting baby and sending the girls off to play for a while til we finished with the poop monster. hahaha they think they are sooo funny.
This pic is my sister walking & holding her daughter and step daughter- she works out. She also has a step son and has had lots of practice with 3 kids at once. My mom also has 3 kids. I am trying to adopt 2 kids who both have ADD and the older one has attachment problems. I am worried about RAD ( Reactive Attachment Disorder) being an issue with her. To add to the fun is the younger ones SI issues so I need to keep an eye out for things he might try to eat, like crayons. He also has food allergies and they both have a long list of doctors and specialists. They were exposed to a wide variety of drugs in utero ( meth, crack, booze, heroin, pot, ...) and are at risk for a variety of health issues. I just found out that they will have caseworkers from DHS, but also from at least one other agency, maybe more, that also assigns them caseworkers, so that they will have 2-6 caseworkers at any given time. I did not get 9 months to prepare for birth and find out about problems, I did not get time with one before the other was born, I did not rack up all the doctors one at a time,.... no I am walking into a maze of caseworkers, and specialists, and problems, and health issues, and emotional issues and reg children's needs -all at once and am a little shell shocked. I don't like coming in late to a test and feeling unprepared so I am playing catch up and soaking up advice while I wait for the dust settles- even from the two experienced laughing hyenas. Whom I had to explain all this to, while asking for help. They think they're so funny, ....I know Mom, I know, bring the plastic bag and distracting toys with me before I start changing him. Where are the wipes?
Did I mention he enjoys throwing dinner on the floor to tell me he is full? He also pulls those suction cup plates off the table, although it does slow him down. - so much for that idea! AND- who made sippy cups that leak when you turn them upside down? What kind of mean joke is that?
I can't wait til they get to visit again! :)

How long after the experiation date can you still use injectible meds? I heard 6 months, is that true?