Biewers naturally have cute little erect ears. When they are young breeders will often use tape to help strengthen the ear. Shaving from the tip of the ear to about a quarter of an inch down the ear is important, this helps take the weight of the hair off the ear and lets it stand more naturally.
It is perfectly natural that you bring home a pup with beautiful erect ears and within a week their ears start to droop down. When some puppies are teething their ears can fall, make sure you keep their ears shaved and they should go back up by themself. If you are really worried, contact your breeder to learn how to tape them properly.
I tell all my new puppy parents to get in the routine of grooming daily, such as the evenings while watching a show. This will help them get used to grooming and from there depending on how you want to keep the coat length that will determine how much time is needed for grooming.
These are the tools I recommend.
It is common in small breeds that an adult tooth comes in and a milk tooth is still retained. This normally occurs in ages three to seven months. The milk tooth and adult tooth are sharing a canal and will build up bacteria, If not caught and removed soon enough the puppies bite could change. If the milk tooth does not fall out naturally, you should contact your vet.