Parent 1 works full time, 4 days a week at home and 1 in the office.
Parent 2 stays at home.
In the morning, parent 1 gets the toddler up, washed and dressed. Parent 2 gets breakfast for everyone and washes it up.
Parent 2 does most daily household chores (cooking, shopping, cleaning).
Parent 1 washes up after dinner and does the 1 year old's full bedtime routine (bath, pyjamas, story, teeth...). Parent 1 also deals with the bins, all DIY and quite a lot of household admin.
YANBU - sounds fair
YABU - not fair