UnderDog

Oy is a chihuahua. He is tiny and bossy, with personal space issues when it comes to other dogs.
Irie is a min-pin, less than a year old, and plays the role of goofy little sister.
Oy was enjoying laptime, and Irie wanted to jump up too, but Oy kept growling and snarling at her to stay down. I grabbed his face and said in a stern voice, "No! You don't get to act like that!"
He stopped growling and Irie jumped up. She started to sit too close to him, and he growled again. I grabbed his face again and said, "No!". He stopped growling and sat very still, while Irie got comfortable.
They sat calmly for a few minutes, and then Irie decided to push her luck:

She scooted up until she was actually sitting on Oy...

I figured Oy would complain and growl for her to get off, but Oy didn't make a sound.

I'd told Oy to be still, and he was obeying. Silently. With deep sighs. He could have hopped down at any time, but laptime is far too important to abandon over a little squishing.

Even when she turned around three times and plopped down on him, he didn't utter a single complaint. 

This type of self control is unheard of in our little dog. I figured he'd really let her have it any second now.

Not a peep! He suffered in silence as this annoying little sister of a dog tried harder and harder to get a rise out of him. He just would not give her the satisfaction.

I felt bad, because Irie was clearly a little brat, and Oy had just resigned himself to being a cushion for her nap. Either one could have jumped down at any time. Eventually, they both just fell asleep.