Like IZ said, I wouldn't worry about the 2yo yet - it's pretty normal for toddlers to be all over the place! They call it "Terrible Twos" for a reason - toddlers are a handful (I don't know how anyone manages them...) And it's not healthy for little growing brains to be pumped full of chemicals. I'm not sure what the guidelines are for diagnosing ADHD in kids, but it seems like you might want to wait until he's about 5, and also see if he's having problems at school as that is often a good indicator. When he's older, there are doubtless techniques you can use to help him if he needs it - learning specialists would be your best asset there, often the best help you can get for kids with ADHD is through a school (aside from meds, that's another matter entirely.) IMO it is probably better to wait; also, ADHD behavior can arise from other causes, like food allergies. My cousin was allergic to Red Dye #5 and was a little hooligan until they figured it out and made sure he didn't eat any of it, then he settled right down and has been a really nice, normal guy.

Have you had any discussions with BF about why he refuses meds? There are a lot of reasons people decide against it, but in my experience there is nothing but relief in the ADHD meds. I'm a lot like that - super flaky and it drives my husband nuts - but it's also very distressing to me to have my ability to function so compromised.

Has he ever tried meds before? Could he be talked into giving it a brief try? If he did try the meds, he would know almost immediately if it helps. I have not run into anyone who has had bad side effects from ADHD meds (unless they didn't actually need them) except if you take them too late in the day or too high a dose, it can keep you up at night. Of course, there are other risks, I'm just saying I've never actually heard anyone mention having side effects.

Hope that helps - good luck!