A rich mother-in-law

A very rich mother-in-law of 3 daughters wants to test her son-in-laws.
On the first day she takes the first son-in-law to a house and she jumps into a pond and cries for help.
The first son-in-law jumps in after her and helps her.
The next morning he sees a new blue BMW parked in front of his driveway with a small note reading...
"Thank you Son, you impressed me... from Mom."

On the second day she takes the second son-in-law to the house and does the same thing.
The second son-in-law jumps in and helps her.
And the next morning he sees a new green BMW parked in front of his driveway with the same note...
"Thank you Son, you impressed me... from Mom."

Finally on the third day she takes the last son-in-law out to the house and does the same thing again, but this time the third son-in-law acted like he didn't know anything and didn't hear anything and she drown and died.
The next morning while the third son-in-law is going out ..
he sees a new red Ferrari parked in front of the driveway with a small note reading...
"Thank you Son, you impressed me... from Dad"