Happy-Tax
Level 5

Via the Form 843, explain and request that the penalty be abated for reasonable cause.

Assuming that the IRS deems the cause to be insufficient, ask that the penalty be abated under the IRS' "First-Time Penalty Abatement" procedures.

Hopefully the forgiveness for cause will work so that the client can keep the "First-Time Penalty Abatement" wild card in her pocket for future use. (The IRS wipes the slate clean after 3 years, so the First-Time Penalty Abatement resets and becomes available again, given time.)