But, Mr Aitken added: "On such a sensitive issue, councils are always the ones left with the difficult decisions between competing priorities."
On the educational attainment of children leaving council care, Eric Jackson, Cosla's spokesperson on social work and health improvement, said that councils are working to rectify the situation but pointed out that the issue could not be seen in isolation.
"We are dealing with kids with complex problems who have to contend with multiple layers of disadvantage. Such children have the decks stacked against them from an early age, and throughout life, which makes prising the education door open extremely difficult."
Mr Jackson said it was imperative to give these children the best possible chance but added: "The real key to the problem is breaking the cycle that leads to the situation where vulnerable children end up in care in the first place."