Running head: Language growth in high-risk siblings. Keywords: autism spectrum disorder, early language development, high-risk siblings, predictors Language growth in very young siblings at risk for autism spectrum disorder. Bruyneel, E. 1 , Demurie, E. 1 , Warreyn, P. 1 , Beyers, W. 2 , Boterberg, S. 1 , Bontinck, C. 1 , Dewaele, N. 1 , Roeyers, H. 1 1 Ghent University, Department of Experimental-Clinical and Health Psychology, Belgium 2 Ghent University, Department of Developmental, Personality and Social Psychology, Belgium Bruyneel Eva – corresponding author Henri Dunantlaan 2 9000 Gent Belgium +32 9 264 64 43 eva.bruyneel@ugent.be Demurie Ellen Henri Dunantlaan 2 9000 Gent Belgium +32 9 264 94 12 ellen.demurie@ugent.be