The government needs to invest at least €54m each year for the next five years to clear hospital waiting lists, according to Barnardos.
The charity said the lives of many children hang in the balance due to a lack of investment in services.
It also wants to see Ireland reach its target of spending 1% of GDP on childhood care and education within five years.
Head of Advocacy June Tinsley said a lack of investment can impede development.
"The reality is childhood is very time limited. We need to ensure there are appropriate services in place to guarantee that children have the childhood that they need, and to enable them to thrive," she said.
"If barriers are placed in early childhood, it really impedes on their development and their ability to reach their potential," she said.
Tusla needs an additional €20m to carry out preventative work, according to a leading children's charity.