Some little tips...
Distraction is a great tool for dealing with older infants and toddlers. Put something in their hand while you examine them and they'll be less likely to pitch a fit. Even preschoolers will respond to distraction.
Examine Mommy first. Temps, BPs, chest assessment... anything the child is likely to resist will be easier if they see Mommy go through it first and see for themselves that she survived. Mom probably won't agree to modelling IV starts though.
Offer preschoolers and older kids choices, but realistic ones only. "Do you want your meds now, or in five minutes?" "Do we do your BP on this arm or the other one?" "Would you like a happy face on your bandaid when I'm done with your test?" But never ask them if it's okay to do something you MUST do.
Meds are often difficult to get into kids. If a parent is experienced at giving their child meds, you might let them do it in your presence. Don't give PO meds to a crying child unless you're comfortable with aspiration. Most liquid meds will go down better if you get them into the back of the child's mouth, past the taste receptors. I like to slip the syringe far back in the buccal pocket and only instill a bit at a time. Otherwise, they let it ooze out their mouth and all over the place. For infants, you can get them sucking on a nipple with a small amount of formula in it, then drop the meds into the open end a little at a time, alternating with formula if necessary. This takes practice. Oh, and prednisone is disguised very nicely in chocolate pudding.
Parents of children with chronic issues often want to do all the things they normally do at home, including central line care, ostomy care, physio and such. If they're around when such care is due, ask them if they want to do it, and respond accordingly. But don't expect them to do it, or "save" it for them. Sometimes we all need a break.
If I think of anything else, I'll be back.