It is recommended to wear it on both ears. The hearing in both ears of the child is within the compensable range of the hearing aid. It would be a pity to give up an ear. Wearing it in both ears has a sound source localization function, which is beneficial to improving the speech recognition rate and preventing hearing loss in one ear without hearing aids.
With appropriate hearing aids and prompt verbal training, your child may be able to speak like a normal child. If there is no intervention, the golden period of children's language development (before the age of 6) will be delayed.
The price of current hearing aids is indeed not low, with more than 1,000 hearing aids being entry-level. Mid-range products generally cost between seven and eight thousand.