We investigate German-Russian bilingual children's sensitivity to formal and semantic cues when assigning gender to nouns in German. Across languages, young children have been shown to primarily rely on phonological cues, whereas sensitivity to semantic and syntactic cues increases with age. With its semi-transparent gender assignment system, where both formal and semantic cues are psycho linguistically relevant, German has weak phonological cues compared to other languages, and children have been argued to acquire semantic and phonological rules in tandem. German-Russian bilingual children face the challenge of acquiring two different gender assignment systems simultaneously. We tested 45 bilingual children (ages 4-10 years) and monolingual controls. Results show that the children are clearly sensitive to phonological cues, while semantic cues play a minor role. However, monolingual and bilingual children have different defaulting strategies, with monolinguals defaulting to neuter and bilinguals to feminine gender.