My first reaction was "Say what?!?" ... and then I thought about it. I'm not saying any of the following are true, but they're all possibilities:
- Rx sleep aids (many different disorders have different pills for daytime and night time). These aren't 'sleeping pills' in the classical sense, but they do have the same effect. As an example, a girlfriend of mine who is as adhd as I am takes trazidone to sleep, and adderall during the day. She gets decent sleep every night... whereas I end up with constant insomnia cycles (I often go to bed between 4am and 6am when I need to turn around and get up at 8am. For many disorders a side effect of EITHER the disorder OR their medication is insomnia. The solution is a 2 med regimen. 1 for waking hours, and 1 shortly before bedtime.
- Rx or OTC single dose pills / aka extended release (many times pills are given at night instead of first thing in the morning so that uncomfy side effects are slept through but the kids get the benefit of them sans side effects the next day).
- Vitamins (many people give or take vitamins at night so that they have longer to absorb before being peed out ... since 70-90% of vitamins are just flushed down the toilet... taking them at night ups the absorption percentage)
- Fast run antibiotics (like zithromax) only needs to be taken for 5 days. If your son was prescribed zithromax (for bronchitis, ear infection, etc.) he may very well have taken a pill every night this week. If the whole family was sick, everyone may have been dosing.
- Worming meds. Often cause upset stomachs (like many Rx's) and are therefore given at night. Again, if 1 person has worms, usually everyone in the house takes them. A few days in a row 1 week, wait a week a few more days in a row.
- Teething. Tylenol before bed happened off and on while my son was a toddler. Cutting molars KILLED his ability to sleep, but bang, just a low dose of tylenol before bed and he was able to sleep comfortably.
- Allergy meds. Since they often make kids *super* drowsy, a great time to give a regularly taken (or sporadic) allergy med is right before bed.
- Oral steroids. For asthmatics and others with severe breathing problems (structural, like asthma, or short term like illness) steroids can be taken either at the end of the day or the beginning.
All of this is assuming, of course, that your toddler is actually recounting things accurately.
Now I'm not saying that his mum ISN'T drugging him with some CPS worthy pill... merely that there are SEVERAL plausible reasons that any or all three children may be taking pills at night.