Families are complicated. Do what you know is right. It sounds like you've got your Mom's best interests in mind and that's the important part. Fight the good fight.
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2009 Bike Friday Season Tikit (commuting folder)
2007 Rivendell Atlantis (touring, general riding, errand runner, stuff hauler)
2007 IRO Mark V (SS)
2006 Rockhopper Comp Disc (Icebike)