Default Language Issue

Hi. Last year my mother bought for herself a Vodafone smart 3. She's happy with it, but the issue that she has with the phone is that she can't change the language of the phone to Ukrainian (She's Ukrainian) because the phone only has English and Spanish. I have tried apps like locale changer and even an app that allows you to change the language of a specific app. All of them were useless, because they changed the language of the apps to Ukrainian, but, the system UI changed to english. Maybe someone knows an answer to solve this issue, thanks for reading my issue.