Is it one or all 4 ?
its for all 4
Do these untie or are they just stretchy/elastic?
they are very stretchy.
Will these fit a newborn?
Yes suitable for 0-6 years
Has anyone tried washing these? I just bought some and wanted to wash them before my baby girl wears them but didnt want to ruin them.
Yep. My little girl sucked on one (teething) then left it in the street. After I finally found it I washed it and let it air dry. No problems at all.
Do these leave marks on your babies head?
They don't , there very strechy
Are they easy for the babies to pull off? I want my daughter to be able to take them off when she gets uncomfortable.
yes they are easy for a child to pull off, my 6 month old pulls hers off.
Washed by hand or machine wash
Hand Wash