six year old no problem yan. mas ok nga mas maaga.
depende sa kakayanan ng bata pero usually within 6 months kaya na nila makipag socialize.
If in cases na medyo hirap talaga, papaulitin sya ng isa level (6 yrs old is either kindy or year 1) ..
And depende rin sa primary school na papasukan nila, usually kapag maraming migrant students, may language teacher para mag assist.
Aware naman ang Govt na madaming family members ng migrants ang nag aaral or mag aaral, kaya available ang various support groups sa school.
Dont worry about it.