The second tab of your friend menu is the Buddy group:



Your buddy group consists of one to three other players who may or not be on your friends list.



The player in the upper slot must be at a higher level than you when you invite them. If they are 20 or more levels above you, you will receive a ten percent bonus - the highest possible bonus. The players in the two lower slots must be at a lower level than you when you invite them, and the same gap bonus applies. The bonus remains the same as you continue to play, even though the level gap will probably change.

As you play the game, you will gain heart coins to increase your daily rewards, which include experience points, pet cash, and buddy points:



You receive:

• 2 heart coins for feeding your animals
  
• 2 heart coins for tending to your animals
  
• 2 heart coins for playing with your animals
  
• 4 heart coins for starting a production in the basement
  
• 6 heart coins for watering plants
  
• 20 heart coins for starting a breeding

As you collect heart coins, your daily rewards increase up to a maximum of 100%, but as you level up, it will take more and more heart coins to get to 100%. You can mouse over the percent display to see the number of points you have and the number required to get to 100%:

Higher buddy group levels will get you greater rewards, including experience points,
Pet Cash, Diamonds, pieces of exclusive new animal species, random cards, and even a store expansion!



You can see the next reward in your main Buddy Group window. Clicking on the little green "i" will show you all available rewards!



When you have rewards to collect, a little heart will appear on the bottom of the friendship button, and selecting the buddy group tab of the friendship menu will cause a pop-up to appear showing you the rewards you earned yesterday: