Your first stages are right on. You are ready to continue to the fur stage. Place in an approximate value background so that you can relate the value of the subject to its surrounding. Otherwise you would be relating the color and value of your pet to a false background which could lead to a too light or too dark rendering. Move on!
This is just beautiful even just in gray tones. You will have an easy time adding the flesh tones as your skill in handling the grays is impeccable. Can’t wait to see the next one!
The addition of color is just wonderful. The grays underneath have tempered the flesh tones so they appear very natural. My only suggestion is to add blush tones on the cheeks in a very subtle way to suggest youth and vibrancy. Good job again.