Estate income received under personal social security number - how to split?

I have collected interest income for my late mother's estate under my personal social security number. This income needs to be split between 3 beneficiaries.  How do I report this to the IRS?

 

Ex. I will be receiving a 1099-INT for $1,920.  However, my portion is only $640 once divided. How do I avoid paying taxes on the remaining $1,280 which was distributed to the other 2 beneficiaries?

 

The IRS says to use a K-1 for estates and trusts.  Is this the appropriate form given that the income was reported under my personal SSN?