Possible Clues:

• Being so old, Mother is impaired by this
• Impair, hurt
• Soundly curse declining years for causing impairment
• Harm, loss
• She gets overtime, but it does her no good
• To vandalise barrier takes a long time
• Cost, slangily
• Mother's put on years, getting injury
• Seems that time is needed to spoil 24 across
• Injury