How hamster behave?

I have several russian dwarf hamsters. My female hamster gave birth last month to a litter of four of which 3 have survived and are now sexually mature themselves. All are housed in separate cages. What I am sharing is based purely on observation of the interaction between my male hamster, Oscar, and female hamster, Minibus: Apart from covering uneaten food in the dish with nesting material every time they finish snacking, both seemed unperturbed by their untidy cage with nesting material (I use roughly shredded toilet paper) all over on their bedding. Then, one early morning I noticed Oscar packing his cheek pouches with the tissue only to deposit it elsewhere in the cage. He had retrieved every bit of tissue from the cage till the area looked as if Housekeeping had come in and made up the room, save the large, well-woven nest at one corner! (Did you know that the nest is woven in such a way that it has "trip wires" to alert its inhabitants of intruders?) Minibus, who did not lift a finger to help in the building of the nest, merely checked it out from time to time. Then, Oscar began wooing her with gifts. The chew stick I dropped into the cage, he placed at Minibus' feet, but she took no notice of it. Bits of food, he would offer her, but she'd reject them. Oscar would stand on his hind legs and stick out his paws like a playful puppy wanting her attention, but she would either squeak at him or pin him down. He would freeze in that position till she backed off. Sometimes, Oscar would sniff Minibus' butt or underbelly but this would get an irritated hiss from her. Other times, he would nuzzle her, they would lick each other's mouths and snouts. Then out of the blue, the cage got really smelly - thanks to Minibus' odorous scent. This whipped Oscar into a frenzy and he began to sniff Minibus' hindquarters to the point of lifting up her backside and chasing her round the cage. The difference between this latest antic and the previous ones is that there were no audible squeaks, hisses or signs of protest from her. :)