WATERVILLE, Maine — This Thursday marks four years since a toddler disappeared from her father’s home in Waterville.

Ayla Reynolds was reported missing on Dec. 17, 2011, by her father, Justin DiPietro.

After a massive investigation, Maine State Police said they don’t believe the little girl is alive. No arrests have been made.

Ayla’s mother, Trista Reynolds, is asking people to honor Ayla this Christmas. According to a Facebook post, she is asking people to light a pink light every night until Jan. 1.

She added that this holiday marks five years since they’ve had a Christmas together.