The official announcement on the producer's instagram.
It's official! Cariba Heine is the H2O: Just Add Water girl to guest star on Mako Mermaids. Here is the official tweet from Johnathan M. Shiff the producer of H2O and Mako Mermaids.
"Welcome home to Mako...RIKKI! A very special guest star #makomermaids #H2OJustAddWater https://instagram.com/p/4x4Onsqa94/
You will see some screenshots from his INSTAGRAM.
I"m so excited! Are YOU?
Cariba's first official Instagram that's public.
Announcement with the mermaids tagged.