Undertired
Also called under-tired, under tired, undertiredness, under tiredness
Undertired describes a baby who hasn't been awake long enough to be ready for sleep, so they resist a nap or bedtime or sleep only briefly. It is the opposite of overtired, and the two can look so alike that parents often can't tell which one they're seeing.
How it's said
Being unable to sleep not being held is one of my baby's biggest undertired signs.
I can't work out if she's undertired or overtired at bedtime, or if this is developmental and I need to ride it out.
Hahaha, yes, it's hard, isn't it? You want them in bed as you have had enough, but they're undertired.
Who says it
Not to be confused with
- An overtired baby has been awake too long and is too wound up to settle. An undertired baby hasn't built up enough sleep pressure yet, and both can look like a baby fighting sleep.
Where it came from
Undertired is made from under and tired as the opposite of overtired. It belongs to talk about sleep pressure: Newton Baby, a baby brand, writes that too much or too little sleep pressure makes a baby overtired or undertired.
The sleep consultancy Little Ones calls under tiredness the far less famous cousin of over tiredness, a place parents end up when they try hard to keep a baby from getting overtired.