“…These reports provide substantial support that early AAC intervention enhances a child ' s communication and language development, from single sign and symbol vocabulary increases for children 3 years old and under (e.g., Adamson & Dunbar, 1991;Barton, Sevcik, & Romski, 2006;Bondy & Frost, 1994;L ü ke, 2014;Wright, Kaiser, Reikowsky, & Roberts, 2013) to multi-symbol utterances and grammatical development for the preschoolers (e.g., Binger & Light, 2007;Harris, Skarakis Doyle, & Haff, 1996). Other reports described the children ' s communication skills, including their communicative turns and functions (Light et al, 1985a(Light et al, , 1985b(Light et al, , 1985c, communication initiations (Letto, Bedrosian, & Skarakis-Doyle, 1994;Dicarlo & Banajee, 2000), and parent-child communication interactions (Pennington & McConachie, 1999;Light, Binger, & Kelford Smith, 1994).…”