Congenital hearing impairment has a negative effect on the social and communication skills in the majority of children. We compared the development of children with various levels of hearing loss who were supplied with hearing aids and children with cochlear implants and those with no hearing problems. We verified the hypothesis about the bidirectional dependency relationship between the tested variables: the influence of mothers’ anxiety on their hearing impaired children’s development and the influence of the children’s developmental level on the anxiety level of their mothers. The participants were 94 children aged 12 to 24 months with various levels of hearing loss corrected with hearing aids or cochlear implants as well as their mothers. The level of anxiety in mothers was assessed using the State-Trait Anxiety Inventory (STAI). A cause and effect relationship was shown between the child’s hearing loss and their development in the communicative area as well as in the social and emotional area. It was found that children with profound hearing impairment with a cochlear implant functioned better than the group of children with similar or lower hearing impairment using hearing aids. The mothers’ anxiety conditioned the child’s poorer development, and the child’s delayed development had an influence on increasing the anxiety level in mothers. The level of profoundness of hearing loss weakens communicative as well as social and emotional development of children. There exists a bidirectional relationship between mothers’ anxiety and their children’s development.