Activists in Aleppo have told ITV News that Bana al-Abed and her mother are fine after concern for their safety grew when her Twitter account disappeared.
The seven-year-old Syrian girl has gained more than 195,000 followers by sharing her daily battle for survival in Aleppo.
The last message from the account was posted by Bana's mother shortly before it disappeared on Sunday.
It read: "We are sure the army is capturing us now. We will see each other another day dear world. Bye - Fatemah".
A search for the account now states the 'page doesn't exist'.
She had also tweeted that her daughter was struggling with illness amid constant bombardment of the besieged rebel-held eastern Aleppo by government forces and Russian allies.
Since the account disappeared many users on the social networking site have been using the hashtag #WhereIsBana.
Desiree Perez says she fears "the worst" having followed Bana's story for weeks, while Caro says she hopes she "reappears in somewhere safer than her current place".
Earlier this month Bana tweeted that her and her family’s home was destroyed by bombing, leaving them homeless.