A low gravity solid tolerant emulsifier and methods of making the same. The emulsifier includes a maleated amido-amine reaction product produced by: (1) reacting a fatty acid material comprising, and an amine material (e.g., a amine having a amine value of about 700 to about 1300 mg/g, such as AMINE HST) to produce an amido-amine reaction product; and (2) reacting the amido-amine reaction product with maleic anhydride to produce the maleated amido-amine reaction product. An invert emulsion fluids and drilling fluids that include the emulsifier of described herein and methods of using the same.