diff --git a/Libraries/Animation/AnimationUtils.js b/Libraries/Animation/AnimationUtils.js
index ac62465a02e219..2ee2d8a7097591 100644
--- a/Libraries/Animation/AnimationUtils.js
+++ b/Libraries/Animation/AnimationUtils.js
@@ -231,8 +231,10 @@ module.exports = {
 
     var tickCount = Math.round(duration * ticksPerSecond / 1000);
     var samples = [];
-    for (var i = 0; i <= tickCount; i++) {
-      samples.push(easing.call(defaults, i / tickCount));
+    if (tickCount > 0) {
+      for (var i = 0; i <= tickCount; i++) {
+        samples.push(easing.call(defaults, i / tickCount));
+      }
     }
 
     return samples;
diff --git a/Libraries/Animation/RCTAnimationExperimentalManager.m b/Libraries/Animation/RCTAnimationExperimentalManager.m
index 64ee577fef30b6..6bcda39ae30d83 100644
--- a/Libraries/Animation/RCTAnimationExperimentalManager.m
+++ b/Libraries/Animation/RCTAnimationExperimentalManager.m
@@ -114,7 +114,7 @@ static void RCTInvalidAnimationProp(RCTSparseArray *callbacks, NSNumber *tag, NS
                   animationTag:(NSNumber *)animationTag
                   duration:(NSTimeInterval)duration
                   delay:(NSTimeInterval)delay
-                  easingSample:(NSArray *)easingSample
+                  easingSample:(NSNumberArray *)easingSample
                   properties:(NSDictionary *)properties
                   callback:(RCTResponseSenderBlock)callback)
 {
diff --git a/React/Base/RCTConvert.m b/React/Base/RCTConvert.m
index a5d2239af57364..9c27b95d98de4f 100644
--- a/React/Base/RCTConvert.m
+++ b/React/Base/RCTConvert.m
@@ -805,7 +805,9 @@ + (UIFont *)UIFont:(UIFont *)font withFamily:(id)family
       for (NSInteger i = 0; i < idx; i++) {
         [(NSMutableArray *)values addObject:json[i]];
       }
-      [(NSMutableArray *)values addObject:value];
+      if (value) {
+        [(NSMutableArray *)values addObject:value];
+      }
       copy = YES;
     }
   }];